ASTM B637
ASTM B637 Basic Info
ASTM B637 specifies the applications of nickel and nickel alloy rods and bars for high-temperature service. These materials, including alloys such as Inconel 718 and Hastelloy X, are widely used in aerospace, gas turbine, and nuclear reactor components due to their exceptional strength, corrosion resistance, and heat resistance. ASTM B637 ensures the quality and reliability of these alloys, critical for maintaining structural integrity and performance in extreme environments.
Characteristics of ASTM B637
- High Temperature Resistance: ASTM B637 materials, such as Inconel alloys, exhibit exceptional resistance to high temperatures, making them suitable for use in environments with elevated temperatures, such as gas turbines, aerospace applications, and industrial furnaces.
- Corrosion Resistance: These materials demonstrate excellent resistance to corrosion, including oxidation, pitting, and crevice corrosion, making them ideal for use in aggressive environments such as chemical processing plants and marine applications.
- High Strength: ASTM B637 alloys typically possess high mechanical strength, allowing them to withstand heavy loads and stress conditions without compromising performance. This makes them suitable for use in critical components subjected to high mechanical stress.
- Versatility: ASTM B637 materials offer versatility in terms of fabrication and application, as they can be easily machined, welded, and formed into various shapes and sizes to meet specific requirements across a wide range of industries and applications.
ASTM B637 Data Sheet
Steel Grade
Dimensions and Tol.
Equivalent Steel Grades
Mechanical Properties
Fabrication and Welding
Steel Grade
Inconel 718
Inconel 725
Inconel 686
Inconel 725LN
Inconel 792
Inconel 625
Inconel 783
Inconel 625LCF
Inconel 693
Inconel 725HS
Inconel X-750
Inconel 690
Inconel 706
Inconel 690LC
Inconel 625PLUS
Dimensions and Tol.
Bars:
Size Range:
Diameter: 0.250″ – 12.000″
Square: 0.250″ – 3.000″
Width: 0.250″ – 6.000″
Thickness: 0.250″ – 6.000″
Hexagonal: 0.250″ – 3.000″
Tolerances:
Diameter: ± 0.005″ to ± 0.030″
Length: ± 1/8″ to ± 1/4″
Width: ± 0.005″ to ± 0.030″
Thickness: ± 0.005″ to ± 0.030″
Hexagonal: ± 0.005″ to ± 0.030″
Forgings:
Size Range:
Diameter: Up to 120.000″
Length: Up to 144″
Width: Up to 120.000″
Thickness: Up to 120.000″
Tolerances:
Diameter: ± 1/8″ to ± 1/4″
Length: ± 1/8″ to ± 1/4″
Width: ± 1/8″ to ± 1/4″
Thickness: ± 1/8″ to ± 1/4″
Wire:
Size Range:
Diameter: 0.010″ – 0.625″
Tolerances:
Diameter: ± 0.001″ to ± 0.005″
Equivalent Steel Grades
United States (USA):
Equivalent Grades: NA21, NA22, NA23
Standard: UNS N07718
European Union (EU):
Equivalent Grades: 2.4668, NiCr19Fe19NbMo3, NiCr19Fe19NbMo3a
Standard: EN 10088, EN 10204
Japan:
Equivalent Grades: NCF 718, NCF 722, NCF 725
Standard: JIS G4903, JIS G4316
China:
Equivalent Grades: GH4169, GH4165, GH4145
Standard: GB/T 14905, GB/T 3077
Mechanical Properties
Tensile Strength:
Condition: Annealed
Value: 140 ksi (965 MPa) min
Condition: Solution Annealed
Value: 185 ksi (1275 MPa) min
Yield Strength (0.2% offset):
Condition: Annealed
Value: 70 ksi (485 MPa) min
Condition: Solution Annealed
Value: 150 ksi (1035 MPa) min
Elongation:
Condition: Annealed
Value: 30% min
Condition: Solution Annealed
Value: 20% min
Hardness (Rockwell C):
Condition: Annealed
Value: 32 HRC max
Condition: Solution Annealed
Value: 40 HRC max
These values represent typical mechanical properties for materials specified under ASTM B637 for nickel-chromium-molybdenum-columbium (Ni-Cr-Mo-Cb) alloys. Actual properties may vary depending on specific requirements, heat treatment, and manufacturing processes.
Fabrication and Welding
Formability:
Nickel-chromium-molybdenum-niobium-cobalt (Ni-Cr-Mo-Cb) alloys specified under ASTM B446 exhibit good formability, allowing for a variety of fabrication processes such as bending, punching, and cutting.
Machinability:
These alloys generally have good machinability, although tooling and machining parameters may need to be adjusted for optimal results.
Weldability:
Nickel-chromium-molybdenum-niobium-cobalt (Ni-Cr-Mo-Cb) alloys specified under ASTM B446 are generally weldable using common welding methods such as TIG, MIG, and SMAW.
Preheating and Interpass Temperatures:
Preheating and interpass temperature control may be required for thicker sections or specific alloys to minimize the risk of cracking during welding.
Post-Weld Heat Treatment (PWHT):
Some alloys may require post-weld heat treatment to restore mechanical properties and improve corrosion resistance.
Welding Consumables:
Matching filler metals and electrodes should be used to ensure compatibility and optimize weld quality.
Welding Procedure Qualification (WPQ):
Welding procedures should be qualified through testing to ensure compliance with applicable standards and requirements, especially for critical applications.
Weld Inspection and Quality Assurance:
Welds should be inspected using appropriate non-destructive testing (NDT) methods such as radiography or ultrasonic inspection to detect any defects and ensure weld quality.
Surface Preparation:
Proper surface preparation, including cleaning and removal of surface contaminants, is essential to ensure sound welds and minimize the risk of defects.
hese considerations provide guidance for fabricating and welding materials specified under ASTM B446 for nickel-chromium-molybdenum-columbium (Ni-Cr-Mo-Cb) alloys effectively.
